中文摘要：

为探索玉米秸秆深翻还田后,土壤中有益微生物的消长动态规律,文中应用传统的土壤微生物学和土壤酶学测定方法,研究常规旋耕秸秆不还田、玉米秸秆深翻还田一年和连续两年玉米秸秆深翻还田等3种耕作方式对土壤有益微生物和土壤酶活性的影响。试验结果表明：玉米秸秆深翻还田可以显著提高土壤有益微生物数量和土壤酶活性;玉米全生育期内,土壤有益微生物数量和土壤酶活性均表现为连续两年玉米秸秆深翻还田（SF-Ⅱ）〉玉米秸秆深翻还田一年（SF-Ⅰ）〉常规旋耕秸秆不还田（CK）,其中,SF-Ⅱ各指标与CK间差异显著（p〈0.05）。SF-Ⅱ对自生固氮菌数量的增幅最高,为157.61%;对土壤脲酶活性的增幅最高,为40.12%。可见,高寒灌溉农区实施玉米秸秆深翻还田耕作措施,既有利于土壤有益微生物的繁殖,也可以提高耕层土壤酶活性。

英文摘要：

In order to Explorate dynamics of beneficial microbes in the soil after maize straw returning, the tradi- tional soil microbiology and soil enzymology methods were applied to study the influence of soil beneficial micro- organism and soil enzyme activities under the three tillage types： conventional tillage, maize straw returning a year and continuous maize straw returning for two years. The test results show that the maize straw returning could significantly improve the soil beneficial microorganism number and soil enzyme activities; soil beneficial microorganism and soil enzyme activities were, SF - Ⅱ 〉 SF -Ⅰ 〉 CK in different treatments during the whole growth period of maize. Among them, each index of SF - I1 had significant difference with CK （p 〈 0.05 ）. The SF- Ⅱ＇s soil nitrogen- fixing bacteria number at the highest level, and increased 157.61% compared with Ck and soil urease activity increased 40.12%. Therefore, the implementation of maize straw returning tillage meas- ures in the irrigation area in alpine region is conducive to the soil physiological groups of microorganisms, could also improve soil enzyme activities of soil.